What are the technical applications of gyro sensors?

For those unfamiliar with such products, the gyroscope sensor is an easy-to-use positioning and control system based on free space movement and gestures. Move the mouse on the plane of the illusion, the cursor on the screen will follow, and you can draw a circle around the link and click the button. These operations can be easily performed when you are speaking or leaving the table.

I have to admit that I had a little trouble at the beginning: because I couldn't operate the two keys at the same time, I was ready to make a support service call. But then I noticed that the instructions were clearly printed on a thin wrapping paper on the AAA battery that powered the mouse. This may be due to oversight or user negligence, but after solving this small problem, the remaining operations are simple.

1GB flash drive

The small USB transceiver on the PC side communicates with the mouse via a 2.4GHz link, and it also has a built-in 1GB NAND memory. Among the components to be analyzed is package manufactured by Micron Technology. It stacks four 256MB SLCNAND chips in a TSOP package, which is a icing on the cake for this already very convenient small mouse. To enable the memory to function as a flash drive, Cypress's controller handles the USB and memory interfaces.

Connecting the controller and memory is Cypress's MCU, which creates half the 2.4GHz wireless link needed to communicate with the air mouse.

The mouse is controlled by the mixed-signal, which has built-in 8KB and 256KB flash memory and 256B RAM.

Beside the DC / DC boost converter, there is also a Cypress.4GHz Direct Sequence Spread Spectrum (DSSS) wireless SoC, which creates the other half of the 2.4GHz wireless link.

Although Cypress's wireless USB devices are always impressive in the field of chips, there is another equally attractive device in the mouse, which is the MG1104 gyroscope module produced by Gyraon.

The MG1104 is very different from the sensors I would expect to see in today's era of silicon MEMS accelerometers. It is particularly large. Its size is close to a large candy module (about 14mm on the side), and it contains many semiconductor materials, but it is only a supplement to the gyroscope sensor itself. The gyroscope operates based on some basic physics principles of the Corioliseffect.

I am reluctant to use the term "fundamental principle" because I have a hard time understanding how the physical structure of a gyroscope applies this principle. The key point seems to be that the Coriolis effect can derive horizontal and vertical velocities from the rotational speed and the oscillations as the gyro disc moves.

The sensor is an etched sheet of metal that forms a complex network of fingers from a driven center point. At first glance, it looks a lot like the old solid sleeve used with 45rpm vinyl records, and can rotate on a standard LP shaft (I know I'm a bit outdated). This sheet of metal is coupled to a drive coil that forms a basic oscillation, while the independent spokes seem to be the monitoring point for another more complex oscillation mode. I'm just as ignorant as poor college freshmen, but the best explanation I can give is that the second oscillation mode of the spokes is affected when the metal plate's initial oscillations form a search acceleration.

Perhaps the actual working principle is somewhat different from the above description (I sincerely hope that readers can correct me), but this mechanical structure is actually a dual-axis acceleration vector source when combined with some signal processing. From this point of view, this custom IC designed by Cadence for Gyraon controls both the op amp and ADC in GYRC10433. Cadence's device reads the detection signal to obtain acceleration data, and then converts it into a serial digital format readable by the module for motion control. The 256B EEPROM stores calibration constants for the module and can be used to compensate for any manufacturing differences.

Drift-free operation

Finally, a very smart step is to provide 4 signal / power connections for the gyro module through a set of oscillating isolation coils that suspend the gyroscope, thereby eliminating drift and inductive positioning errors.

Although the product is designed for speakers using PowerPoint, the gesture-based control concept has expanded into many other areas, including PC-based TV remotes. In fact, Gyration would be very happy if it cost you about $ 100 to buy a WindowsMedia-compatible GY3101A universal remote control. This gadget for consumer applications uses basic Gyrotransport technology.

It is worth mentioning that the area of the original silicon chip dedicated to the FreeSpace core functions of this product is nearly 6 cm2 less than the area required for a 1GB NAND memory. Although the storage function of GyraTIon products is an additional function to increase attractiveness, the actual silicon area of the memory has a lot of room for discussion.

The above disassembly analysis only shows that the powerful functions of products often come from relatively small chips, as is the case with gyro modules, and the main functions of products come from parts that have little to do with silicon chips.

If you want to know more, our website has product specifications for sensor， you can go to ALLICDATA ELECTRONICS LIMITED to get more information